Add a copy of the Linux License, for its 2.4 version, as detailed in https://www.gnu.org/licenses/gpl-howto.en.html:
> If you have copied code from other programs covered by the same license, copy their copyright notices too. Put all the copyright notices for a file together, right near the top of the file.

C Language ISO standard makes a warn on keeping the qsort comparision function out of modifying array's data. Make a case of that, lifting up the element flagging. Because flag is probably drawn back by other means that better accomplish the same purpose and are already in place, just drop this flag away rather than moving it anywhere else. Ref.: 7.20.5 Searching and sorting utilities

modify interfaces in accordance with: 
- void add_class_def(struct type_id_st *class_idx, struct type_id_st *super_class_idx, struct type_list_st *super_iface_lst);
- lgwseq_t *for_lgwseq(size_t lg, const wchar_t *from);
